package com.shux.common.biz.impl;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.font.FontRenderContext;
import java.awt.geom.Rectangle2D;
import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.Random;

import javax.imageio.ImageIO;

import org.apache.shiro.SecurityUtils;
import org.apache.shiro.session.Session;
import org.apache.shiro.subject.Subject;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.context.annotation.Scope;
import org.springframework.stereotype.Service;

import com.shux.common.biz.ISecurityBiz;
import com.shux.utils.constants.Constant;

/**
 **********************************************
 *  描述：
 * Simba.Hua
 * 2017年5月29日
 **********************************************
**/
@Service("securityBiz")
@Scope("prototype")
public class SecurityBizImpl implements ISecurityBiz {
    private Logger logger = LoggerFactory.getLogger(getClass());
    @Override
    public ByteArrayOutputStream generateCode() {
        ByteArrayOutputStream output = new ByteArrayOutputStream();
        String code = drawImg(output);

        Subject currentUser = SecurityUtils.getSubject();
        Session session = currentUser.getSession();
        session.setAttribute(Constant.SESSION_SECURITY_CODE, code);
        return output;
    }

    private String drawImg(ByteArrayOutputStream output) {
        String code = "";
        for(int i=0;i<4;i++){
            code += randomChar();
        }
        int width = 70;
        int height = 25;
        BufferedImage bi = new BufferedImage(width,height,BufferedImage.TYPE_3BYTE_BGR);
        Font font = new Font("Times New Roman",Font.PLAIN,20);
        Graphics2D g = bi.createGraphics();
        g.setFont(font);
        Color color = new Color(66,2,82);
        g.setColor(color);
        g.setBackground(new Color(226,226,240));
        g.clearRect(0, 0, width, height);
        FontRenderContext context = g.getFontRenderContext();
        Rectangle2D bounds = font.getStringBounds(code, context);
        double x = (width - bounds.getWidth()) / 2;
        double y = (height - bounds.getHeight()) / 2;
        double ascent = bounds.getY();
        double baseY = y-ascent;
        g.drawString(code, (int)x, (int)baseY);
        g.dispose();
        try {
            ImageIO.write(bi, "jpg", output);
        } catch (IOException e) {
           logger.error("ImageIo write jpg picture error!",e);
        }
        return code;
    }

    private char randomChar() {
        Random random = new Random();
        String s = "ABCDEFGHIJKLMNPQRSTUVWXYZabcdefghigkmnpqrstuvwxyz123456789";
        return s.charAt(random.nextInt(s.length()));
    }

}
